1. Field of the Invention
The present invention relates to an active matrix-type display device comprised of liquid crystal cells or other display elements of pixels (electrooptic elements) arrayed in a display region in a matrix and a method of driving the same.
2. Description of the Related Art
Display devices, for example, liquid crystal display devices using liquid crystal cells for the display elements of the pixels (electrooptic elements), feature thin profiles and low power consumptions. Utilizing these features, they are being used in, for example, personal digital assistants (PDAs), mobile phones, digital cameras, video cameras, personal computer-use display devices, and other electronic devices.
FIG. 1 is a block diagram showing an example of the configuration of a liquid crystal display device (for example, see Japanese Patent Publication (A) No. 11-119746 and Japanese Patent Publication (A) No. 2000-298459). The liquid crystal display device 1 has an effective pixel section 2, a vertical drive circuit (VDRV) 3, and a horizontal drive circuit (HDRV) 4.
The effective pixel section 2 is comprised of a plurality of pixel circuits 21 arrayed in a matrix. Each pixel circuit 21 is configured by a thin film transistor (TFT) as a switching element, a liquid crystal cell LC with a pixel electrode connected to the drain electrode of the TFT (or source electrode), and a storage capacitor Cs with one electrode connected to the drain electrode of the TFT. For these pixel circuits 21, scan lines (gate lines) 5-1 to 5-m are arranged along the pixel array direction for the rows and signal lines 6-1 to 6-n are arranged along the pixel array direction for the columns. Further, gate electrodes of the TFTs of the pixel circuit 21 are connected in row units to the identical scan lines 5-1 to 5m. Further, the source electrodes of the pixel circuits 21 (or drain electrodes) are connected in column units to the identical signal lines 6-1 to 6-n. 
Further, in a general liquid crystal display device, a storage capacitor line Cs is arranged independently. Storage capacitors Cs are formed between the storage capacitor line and first electrodes of the liquid crystal cells LC. The storage capacitor line Cs receives as input a pulse in-phase with the common voltage VCOM and is used as a storage capacitor as well. In a general liquid crystal display device, the storage capacitors Cs of all pixel circuits 21 in the effective pixel section 2 are connected in common to one storage capacitor line Cs. Further, the second electrodes of the liquid crystal cells LC of the pixel circuits 21 are connected in common to, for example, a supply line 7 of the common voltage Vcom inverting in polarity with each horizontal scan period (1H).
The scan lines 5-1 to 5-m are driven by the vertical drive circuit 3, while the signal lines 6-1 to 6-n are driven by the horizontal drive circuit 4.
The vertical drive circuit 3 performs a scan in the vertical direction (row direction) at each field period and successively selects pixel circuits 21 connected to the scan lines 5-1 to 5-m in row units. For example, when a scan pulse SP1 is given to the scan line 5-1 from the vertical drive circuit 3, pixels of the columns of the first row are selected, while when a scan pulse SP2 is given to the scan line 5-2, the pixels of the columns of the second row are selected. In the same way below, the scan pulses SP3, . . . , SPm are given in sequence to the scan lines 5-3, . . . , 5-m. 
FIG. 2A to FIG. 2E are timing charts in a so-called 1H Vcom inversion drive unit of the general liquid crystal display device shown in FIG. 1.
Further, as another drive unit, a capacity coupling drive unit using coupling from the storage capacitor line Cs and modulating the voltage applied to the liquid crystals is known (for example, see Japanese Patent Publication (A) No. 2-157815).
The above-explained capacity coupling drive unit, in comparison to the 1H Vcom inversion drive unit, can improve the response speed of the liquid crystals by so-called overdrive and further can reduce audio noise generated by the Vcom frequency band and perform contrast compensation (optimization) etc. in superhigh definition panels.